Java操作XML文件(2)-读取XML文件
使用Java读取XML文件：
package xml;import java.util.ArrayList;import java.util.List;import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;import org.w3c.dom.Document;import org.w3c.dom.Element;import org.w3c.dom.NodeList;public class XMLReader {private String fileName;public XMLReader(String fileName) {this.fileName = fileName;}public Element getRootElement() throws Exception {DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = factory.newDocumentBuilder();Document document = builder.parse(fileName);return document.getDocumentElement();}public List<Element> getElementsByTagName(Element parent, String tagName) {List<Element> elements = new ArrayList<Element>();if (parent != null) {NodeList list = parent.getElementsByTagName(tagName);for (int i = 0; i < list.getLength(); i++) {elements.add((Element) list.item(i));}}return elements;}public Element getElementByTagName(Element parent, String tagName, int index) {List<Element> elements = getElementsByTagName(parent, tagName);if (index < 0 || index >= elements.size()) {return elements.get(0);} else {return elements.get(index);}}public String getTextContent(Element e) {return e.getTextContent();}public String getAttribute(Element e, String name) {return e.getAttribute(name);}public static void main(String[] args) {try {XMLReader reader = new XMLReader("E:\\test.xml");Element root = reader.getRootElement();System.out.println(reader.getElementsByTagName(root, "Book").size());Element book = reader.getElementByTagName(root, "Book", 0);Element price = reader.getElementByTagName(book, "Price", 0);System.out.println(price.getTextContent());Element title = reader.getElementByTagName(book, "Title", 0);System.out.println(reader.getTextContent(title));System.out.println(reader.getAttribute(title, "Auth"));} catch (Exception e) {e.printStackTrace();}}}